This invention relates to a printing machine in general, and more particularly to a paper feeding mechanism for use in a printing machine designed to transport the paper to be printed substantially in a linear path from a paper inserting port to a paper feed-out port.
FIG. 1 diagrammatically shows the prior art printing machine of so-called wire-dot impact type, in which a printing paper 2 is supplied from an inlet 3 provided in the rear (i.e., at the right in FIG. 1) of the machine 1, and is transported in the direction of the arrow A by means of a platen 4 and then is guided to the outside through an outlet 7 also provided in the rear of the machine 1. In the meantime a printing head 6 is operated to print the paper 2 by means of an intermediate ink ribbon 5. In this case, as shown, the paper 2 travelling inside the machine 1 will describe substantially a U-shaped path turning around the platen 4, and thereby it has often been failed to smoothly transport the paper 2. Moreover, paper 2 would contact with ink saturated members of platen 4 in a wide area, resulting in a great probability that the paper would be undesirably contaminated by ink. Furthermore, paper 2 has to be inserted into the machine 1 through the inlet 2 with its normal side down. This may be a serious inconvenience especially when the printing side has been provided a graph in which some characters must be printed, as the operator can not refer to the graph for properly printing the characters in a definite position in the graph as required. Moreover, it has been inevitable that a device for supplying a long continuous printing paper must be positioned in the rear of the machine 1, resulting in that a desk or the like on which the machine 1 has to be placed is required to provide a sufficient space rearwardly of the machine.